Helpin OOP

Please I need help solving this Oval and FilledOval code by changing the instance variables in Oval that are in public, which is not optimal, to private and re-implement any code that depended on the public accessibility of those instance variables. Here is the code:

import java.awt.*;

public class Oval { public int x, y, w, h;

public Oval(int x, int y, int w, int h) {
    this.x = x; this.y = y; this.w = w; this.h = h;
}

public void draw(Graphics g) {
    g.drawOval(x,y,w,h;
}

public int getWidth() { return w; }

public int getHeight() { return h; }

public Point getTopLeftPoint() { return new Point(x,y); }
//...other methods...

}

public class FilledOval extends Oval { public FilledOval(int x, int y, int w, int h) { super(x, y, w, h); }

public void draw(Graphics g)
{
    g.fillOval(x, y, w, h);
}

}